The drum (or operating chamber) of known front loading or top loading laundry washing machines and washer-dryers is accessible by an access opening provided in the cabinet of the machine and closable by a door, for example hinged to the cabinet.
The door is provided with a closing hook, called also “hook member” or simply “hook”, that engages with an electro-mechanical door locking device mounted internally to the cabinet and arranged in such a way to be accessible by the hook when the door is in the closed position. The closing hook is part of a mechanical lock which is operable by means of a handle by the user.
When the door is in the closed position, the hook protrudes from the surface of the door facing the cabinet of the appliance, and it is hinged to the door and positioned in such a way to enter into a corresponding opening provided in the door locking device and accessible from outside the cabinet via a corresponding through opening formed in the cabinet.
The hook is urged, for example by means of a spring, towards the border of the opening of the door locking device in a closing position in which it keeps the door fixed to the cabinet; the door handle is mechanically connected to the hook and it is arranged in such a way to move it from above closing position to an opening position in which the hook does not match the border of the opening of the door lock, so as to allow the opening of the door.
The electro-mechanical door locking device generally comprises a mechanism for the instantaneous interlock and/or delayed release of the door, called the door interlock, which has the function of preventing opening of the door after the machine has been started and/or of delaying opening thereof at the end of the working cycle, for example to ensure that the inertial rotation of the drum has ceased, or that the inner temperature has decreased enough.
The electro-mechanical door locking device comprises a retaining member which is coupled in a sliding manner to a support housing of the door locking device. The retaining member is mounted to move with respect to the support housing between a rest position in which it enables the hook member to be introduced into and extracted from the opening of the door lock, and an operating position in which it retains the hook member in a closing position, when the hook member is introduced into the opening of the door lock.
In addition, the door locking device generally includes a safety member, e.g. a safety pin, a safety member which can move in the support housing between a retracted position, in which it enables the retaining member to move from the operating position to the rest position, and an extended position, in which it prevents the retaining member from moving from the operating position to the rest position.
This door locking device is controlled by electronics which need power supply in order to operate properly. In other words, in case of a sudden or not foreseen lack of electric supply, if the door locking device is in a locked status preventing the opening of the door, it remains in such a status till the power supply is available again. In details, if a power failure occurs when the safety member keeps the door locking device in its locked configuration, there is no way of opening the appliance door without damaging the door locking device forcing the same.
It is well known that such emergency conditions occur. In these situations, it is therefore necessary to act from outside the appliance in order to open the door locking device if it is in a closed state with the door of the appliance closed on the cabinet.
Some emergency openings are known in the art. For example, an emergency opening is made by intervention of the maintenance service, opening the appliance and/or lifting the same in order to access an unlocking mechanism of the door locking device, which is actuated by a cord or the like provided within the appliance.
Examples of known documents describing household appliances provided with door locking emergency openings are as follows.
DE 3006307 in the name of Miele & CIE describes a washing machine which includes a safety unlocking device for opening the door, provided at the boundary of the same, under the ring. The unlocking is actuated by the insertion of a tool between the door ring and the front wall of the washing machine.
EP 2159316 in the name of the Applicant describes a laundry washing machine having a safety lock device being fixed to the first wall aligned with the first opening, and having a latch element between an unlock position in which said latch element does not engage the catch element, and a lock position in which said latch element engages the catch element fitted into the first through opening; the manual release of the door from the machine casing being subordinated to the movement of said latch element from the lock position back to the unlock position and the safety lock device also having an axially movable lock pin, which is movable between an extracted position in which the lock pin engages the body of the latch element to prevent the latch element from returning into its unlock position, and a withdrawn position in which the lock pin does not engage the body of the latch element and allows free movement of the latch element; the first wall of the casing having a safety through opening by which to insert an emergency-opening tool inside the machine casing to force the lock pin from the extracted position to the withdrawn position.
EP 2251479 in the name of Bitron S.p.A. relates to a household appliance provided with a door, comprising a door-locking device of the kind provided with an element for permitting activation of emergency opening of said door, and an emergency opening system for said door-locking device, said household appliance being characterised in that it provides a slot, realized on its outer wall, and in that said system comprises a tool, that can be inserted through said slot until interacting with said element in order to permit activation of the system for emergency opening of said door.